Multi-'omics of gut microbiome-host interactions in short- and long-term myalgic encephalomyelitis/chronic fatigue syndrome patients.
Xiong, Ruoyun, Gunter, Courtney, Fleming, Elizabeth et al. · Cell host & microbe · 2023 · DOI
Quick Summary
Researchers studied the gut bacteria and blood chemicals of people with ME/CFS to understand how the disease affects the body. They compared three groups: people with ME/CFS for less than 4 years, people who've had it for over 10 years, and healthy people without the disease. They found that early ME/CFS patients have significant changes in their gut bacteria, while long-term patients' bacteria had mostly normalized, but their blood chemistry and symptoms remained abnormal.
Why It Matters
This research provides evidence that ME/CFS involves measurable changes in gut bacteria and blood chemistry, offering potential biomarkers that could help diagnose and monitor disease progression. Understanding how these microbial and metabolic changes relate to ME/CFS symptoms may eventually lead to targeted treatments.
Observed Findings
Short-term ME/CFS patients showed significant microbial dysbiosis compared to controls, while long-term patients had largely restored microbial composition.
Both ME/CFS cohorts demonstrated reduced plasma levels of butyrate, bile acids, and benzoate compared to healthy controls.
Microbial butyrate biosynthesis capacity was reduced in ME/CFS patients, correlating with low plasma butyrate levels.
Phenotypic, microbial, and metabolic biomarkers were identified that distinguished between short-term and long-term disease cohorts.
Metabolic dysbiosis persisted in long-term patients despite normalization of microbial dysbiosis.
Inferred Conclusions
ME/CFS involves distinct microbial and metabolic dysbiosis patterns that differ by disease duration, suggesting different biological mechanisms in early versus established disease.
Reduced microbial butyrate production and plasma butyrate levels represent potential functional mechanisms underlying ME/CFS pathophysiology.
Persistent metabolic abnormalities despite microbial recovery in long-term patients suggests that metabolic disruption may be a more stable feature of chronic ME/CFS.
Remaining Questions
Do the observed microbial and metabolic changes cause ME/CFS symptoms, or are they consequences of the disease and its effects on lifestyle and physiology?
What This Study Does Not Prove
This study does not prove that gut bacteria changes cause ME/CFS or that restoring bacteria will cure the disease—it only shows associations. The cross-sectional design means we cannot determine whether these changes precede symptom onset or result from the disease itself. Nor does it establish whether the metabolic abnormalities in long-term patients are irreversible or could be therapeutically addressed.
Could interventions targeting butyrate production or other depleted metabolites improve ME/CFS symptoms, and would this occur in both early and chronic disease stages?
What drives the apparent "recovery" of microbial composition in long-term patients while metabolic dysfunction persists?
Are the identified biomarkers specific to ME/CFS or shared with other chronic illnesses involving fatigue and post-exertional malaise?